Gunfire synchronizing control



July 9, 1946.

F. JAN W. DEN OUDEN GUNFIRE SYNCHRONIZING CONTROL Filed March 50, 1944FIEJ INVENTOR I2 52/ 4) 14444.5 oz-w 0006A w. v e

rae vt s Patented July 9, 1946 UNITED stair-Es PATENT", ems-E 1FritsJan-Willem den Ouden,

Melbourne,

' Victoria, Australia .ApplicaticntMarch 30, 1944,;SeriaLNoh528L759 3Glaims: (01 89 28) Theinyention. described.- hereintmay. bemanufacturedandused by or for. Government for governmental purposes,Without the-payment tome of any royalty thereon.

This invention relates to. improvements in gun fire control apparatus,and moreparticularly, to means for synchronizing the fire of .apluralityof automatically operable guns.

An. object of the invention. is thehprovi'sion of. means forsynchronizing fireofca plurality of automatically operable. guns. offthe machine. gun type by controlling th discharge. of the gunsby thereloadingoperation'otone of the guns.

In multiple machine gunmounts, such asthose used inturrets of.airp1anes-and-thelike, ithas been found that therezisa-considerablewaniation in. the. accuracy of fire. from-these-guns,depending,upon whether the gun are firedinesynch-ronism on not, this,being especiallyv truea Where the guns are mounted in turrets; in'tandemmounts. The. rate or fireof: these. machineguns-isl-ad-justable,but-since these guns, after the" triggers. are actuated, fire andreloadindependently or each other, it is practically impossible to: adjustboth guns to fire exactly the; same number of roundsper minute,andeonsequently; iffthertriggersgare depressed for a prolonged burst offire, the guns are: soon firing out of. 'synchronism' with each other.Apparently, the reooilr o shock oithe iaster firing gun causes the mountand turret to: be vibrated and this shock; is; communicated to theotheror slower firing; gun,.reducingthe accuracy of this latter gun; andconsequently, the corresponding subsequent-explosion of'. the slower:firing. gun then similarly a-fiects the'accuracy or bullet dispersionfollowing-the subsequent explosion of the. cartridge in. the fasterfiringegun.

In. addition to the: above, these machine guns are usually mounted inthe turretsla't eitherside of a vertical plane passing betweerrlthezgunsthrough the" center of: the tulreuoand any-slight play-'01" resiliencyexisting in: thelturret rotating mechanismf'will cause the: alternatefiring of the two guns, when: they are out ofi synchronism-,-. toproduce aslight oscillatory motion of -the turret with a. correspondingincrease in thexbiilletr-dispersion area. and. a markeddecreaseinithgsac curacy of. fire. It haszbeenfound that tha area of: bulletdispersion between two machine; guns in a turret mount, when firing insynchrom'sm, may be as. little as one-sixth ofwtheflbullet dispersionarea when theguns are firing out-of synchrom'sm. 3 l

A further object. of theinvention is thezprovia sion of means forcontrolling the firing opera-- tion of a plurality of machine guns iniacommon or: multiple gun mount. so that-the dischargeof the faster firingguns is controlled by th'etoper: ati'onof the slowest firing'glm; I

A still further object i jthe provisiortof'agun fire control system forremotely controlled tandem mounted machine guns fl'ravin'g relativelydifierent ratesjof" firein which means. are. pros Viligi. for. retardingthe discharge. oi. the"fa'ster firing, .gun by. the gun loadingoperation offth'e slowen'firing gun. g

.Arfurther' object is -the.provi'si0n, auniultiple ma'ehihegun'firingremotely controlled apparatus having. a, plurality of.machineq'guns firing, and reloading in different time uperio'ds',orz'm'eainsf which includes a. common gunfiriiig; contrblbit-j cult. forsaid guns and circuit interrupting means operable T; to. interrupt the,firingr circuit Of" all, of theguns whenfthe slowerifirihgglln is not.in gun firinaposl'tionl f Another. object. of the invention is tocontrol 7/ the firing. operation of one gun or remotely controlledtandem. mounted; machine.- guns by? the position of'the. hreecl'rbolt'of. the. other gun.

.Other objects andia'dvantages of. the invention will become apparentinl the. following. description takenin; connectionwith tlieaccompanying drawing in which. like reference;eharacters..refertolikepartsohthe severalI-figures. H

.Fig..1 isfa somewhat diagrammatic. perspective viewf disclosing atandem. gun. mountlof theft'urrettype.:having .lmyI improved? gun. firesynchro- I nizing control'incmporatdthereihi and schemat icallyillustrating a I.wiring;,.diagram for the {remote firercontrolof.theIguns. V I

Fig, 2 is, a: fragmentary.(diagrammatic Viewllfll lustrating the.trigger release mechanism'iof; a machine gun, and .eleetroemagneticmeans for. actuatingthetrigger tofire thegun.v 1 r Referringparticularly to'Fig; 1 of; thegdrawa ing, the .numeraL Lindicatesa gun.turret; such as used. in air planes and the dike, havingra rack orring;gear. A pinion: 3. is, disposed; immeshing,

' relation with the rack for. rotatablyfadfiusting the. turret. underthe controls off a suitablespower driven adjusting mechanism (notlshownrThe turret carries a tandem. or, multi-gummountd on, which? arepositioned the right-hand,-- and'lefthand: maehinegunst 5 and, 6...Each-of the ;guns 5 and-.- 6: is provided; with" a trigger, asindicated. in. th eldrawing. at 541. and.- 6a,, respectively,andthesetriggers I. are actuated by trigger actuating. solenoids'LandB.I

. Each cftheguns. Sa'ndf fiiisloithe conventional.

machine gun type, as disclosed in Patents ,5 nd reference being made tothese patents for the internal firing and loadin mechanism of the guns.

Referring now to Fig. 2, the guns each have a breech bolt 9 carrying afiring pin II] which, when cooked, is engaged by a vertical sear memberI i normally held in raised lat ing position by the spring l2 to preventthe firing pin from exploding the cartridge in the barrel. Actuation ofthe trigger 5a (or 6a) rocks the sear actuating memher or trigger bar l3to depress the sear ll, releasing the firing pin ID in the usual manner.When the trigger is held depressed or in firing position, the camportion l3a depresses the sear l3 as the breech bolt moves forward,releasing the firing pin to fire the fresh cartridge inserted in thebarrel incident to the auto-loading action of the gun. The energizing ofthe solenoid 1 (or 8) moves and holds the trigger 5 (or 6) in firingposition.

In carrying out my invention, I provide a laterally extending projectionM on each of the breech bolts 9 of the machine guns 5 and 6. Theseprojections extend through guide slots in the receivers of the guns 5and 6. When the guns are in firing position these projections aredisposed in the forward ends of the slots I5, as indicated in Fig. 1 ofthe drawing. The normally open microswitch I6 is secured to the side ofthe re-. ceiver of the gun 5 in advance of the laterally extendingprojection l4 so as to be actuated by this projection when the breechbolt 9 of the gun is in its forward or firing position. The machine gun6 also has secured to the receiver a normally open microswitch l1arranged to be closed by the laterally extendin projection M on that gunwhen the breech bolt is in firing position. Electrical conductors l8 andI!) are connected respectively to one terminal of each of themicroswitches l8 and I! while the other ends of the conductors areconnected with-the trigger actuating solenoids I and 8, the otherterminal of each solenoid being grounded to the frame or. gun mount, asindicated at and 2!. The other terminals of the two microswitches l6 andI1 are connected by the conductors 22 and 23 to one end terminal of eachof the gun fire synchronizing control switches 24 and 25. The other endterminals of the switches 24 and 25 are respectively connected by theconductors 26 and 21 to a common feed wire or conductor 28, leading froma battery or other electrical power source 29. The remote gun controlcircuit, including the conductors 30 and 3| and the fire control button32 is interposed in the conductor 28 between the gun firingsynchronizing control switches 24 and 25 and the battery 29; the otherside of the battery is connected or grounded to the frame or gun mountin the usual manner, as indicated at 33.

A conductor 34 is connected at its ends to the conductors l8 and i9 atsome point intermediate the microswitches l6 and I1 and the solenoidcoils 'I and 8, which are connected respectively to the conductors l8and IS. The common feed wire or conductor 28 is connected to the groundor gun mount at 35 by a conductor 36, having a condenser 31 interposedbetween the ground and the conductor to prevent sparking at themicroswitch circuit closing terminals. The conductor wire 28 is alsoconnected to one end terminal of a circuit controlling switch device 38,while the other terminal of the switch device is connected by aconductor 39 to the conductor 34 between th 4 wires I8 and [9 leading tothe microswitches l6 and H. A conductor wire M1 is connected to theother terminal of the switch device 38 at one end and grounded at theother end as indicated at 4|, and has a condenser 42 interposed in itslength between its end connections.

In the operation of the device it is first necessary to determine whichof the guns isthe slower firing gun. In the event of a multi-gun mountcarrying three or more guns, the slowest firing gun must be determined,since this is the governing gun for the firing operation of the otherguns, and once this has been determined, one of the synchronizingcontrol switches 24 or 25 in circuit with the microswitch on thereceiver on the slower firing gun will be closed, energizing the circuitincluding the solenoid trigger depressing mechanism and the microswitchfor the slower firing gun.

Assuming that the machine gun 5 has been found to fire 700 rounds perminute while the gun 6 only fires at the rate of 650 rounds per minute,the gun 6 is therefore the slower firing gun. The switch 25 is thenclosed, as shown in full lines in Fig. 1. When the guns are at rest andloaded, both breech bolts will be in their forward positions with thefiring pins l0 cooked or retained in their firing position by the searsH,- and the breech bolt extensions 14 will be resting against theplungers which actuate the microswitch circuit closing contacts of themicroswitches I6 and l1, maintaining these switches closed and incurrent-passing positions.

Upon the actuation of the main fire control button 32, current will fiowfrom the battery 29 through the conductor wires 3| and 30, main feedwire 28, conductor wire 21, across the now-'- closed synchronizing"control switch 25 and con-'- ductor 23 to the microswitch l1. Sinceboth'the" breech bolts will be in their forward positions before theguns are initially discharged, the microswitch I! will be closed,allowing current to flowthrough the conductor wire IS to the solenoid 8,across the wire 34, energizing the other solenoid device I, causing boththe triggers 5a and 5a of the guns 6 and 5 to be depressed, and the gunswill be simultaneously fired. The above mentioned firing circuit iscompleted between the other terminals of the solenoids 1 and 8throughthe ground connections 28 and 2|, constituting the metallic framework ofthe turret or gun mount, the current returning to the other side of thebattery 29 through the ground 33 between the battery and the frame.

Since the gun 6 is assumed to fire and reload slower than the gun 5, thebreech bolt of the. gun 5 will not return to firing position as soon asthe breech bolt of the gun 5, and since the? microswitch I! will not beclosed until th'ebreech bolt of the gun 6 has moved to its forwardfiring. position, the circuit at both solenoids will be open, preventingeither of the solenoids I or 8 from depressing the-triggers 5a. or Go ofthe guns until the breech bolt of the slower gun 6 moves to its. formerfiring position. As the breech bolt of the gun 6 moves forward to thefiring position,'the microswitch I1 is again closed, energizing thecontrolling circuit just described, causin the solenoids I and 8 tubesimultaneously energized, depressing the triggers and firing both gunsin synchronism. e

In the event that the other gun 5 was found to' be the slowerfunctioning of the two guns 5 and 6, the switches 25 and 38 wouldbe leftopen and the switch 24 connecting the conductor 22 leading to themicroswitch IS on the gun 5 would be closed. Under these conditions, thefiring of the gun 6 would be delayed or retarded after each explosionuntil the breech bolt of the gun 5 has moved forward to its subsequentfiring position, closing the circuit through the conductors I8, 22 and34 to the two trigger actuating solenoids l and 8, causing both guns tobe fired simultaneously.

When it is desired to fire the guns independently of the synchronizingmechanism for any reason, such as to initially determine which is thefaster firing gun, or in the event that the slower firing gun hadjammed, the switch 38 is closed. The closing of this switch establishesa circuit from the battery 29 through the gun fire control button 32across switch 38 and conductor 39 to the conductor 34 connected to bothof the solenoids I and 8. Both triggers 5a and 6a will be simultaneouslydepressed and remain depressed as long as the main fire control switch32 is held closed by the gunner. Should either gun be jammed the othergun will continue to fire.

It has been found that where two or more machine guns are mounted on amulti-gun mount in a power driven turret employing my improvedsynchronizing system, by utilization of the slower firing gun to delaythe discharge of the other or faster firing gun or guns until the breechbolts of all the guns are in firing position, and then simultaneouslyfiring all the guns, I am able to efiectively maintain the discharge ofall the guns in synchronism, and that the area of bullet dispersion isabout one-sixth the bullet dispersion area when the guns are allowed tofire independently or out of synchronism. The oiT-center recoil or shockof the guns on the turret drive mechanism is also eliminated, making itpossible to reduce the power necessary to smoothly rotate the turretduring the firing operation of the guns, as well as to reduce the amountof force necessary to hold the gun sighted on the target. The greatreduction of the bullet dispersion area by my improved device isequivalent to firing on a target 400 yards away as compared to firing ona similar target 1000 yards distant with the conventional gun turretsnow in use without my improved synchronized fire control.

While the construction and arrangement of the invention herein describedand illustrated is that of a generally preferred form, obviously,modifications and changes may be made within the scope of the appendedclaims without departing from the spirit of the invention.

I claim:

1. In a gun fire control system for synchronizing the gun firingoperations of a plurality of machine guns, a plurality of machine guns,a movable part carried by each gun movable to a gun firing positionbefore the gun can be fired and movable to a recoil position incident tothe firing of the gun, an electro-magnetic firing control mechanismconnected to each gun for initiating the firing operation of that gun,an electrical energizing firing control circuit including theelectro-magnetic firing mechanisms of all of the guns and operable whenenergized to simultaneously energize said electro-magnetic firingmechanisms to fire all of said guns simultaneously, a normally opencircuit closing switch carried by each gun, at least one of saidswitches being connected in said firing control circuit to normallyinterrupt the circuit, switch actuating means carried by the movablepart of each gun position to close said normally open circuit clos- 4ing switch, and movable to switch disengaging position by said movablepart when said movable part is in recoil position to allow said normallyopen circuit closing switch for that gun to move to its normally openposition to interrupt said firing control circuit to prevent the firingof said guns. V

In a gun fire synchronizing control system, at least two machine guns,one of whichfires at a slower rate than the other gun, a movable recoiloperated breech block for each gun movable forwardly to gun firingposition and rearward to recoil position incident to the firingoperation of the gun, a trigger means on each gun for firing said gun,magnetic actuating means on each gun engageable with said trigger meanswhen said magnetic actuating means is energized to actuate the triggermeans to fire said gun, an electrical firing control circuit connectingthe said magnetic actuating means of all of the guns to simultaneouslyactuate all of said magnetic actuating means to simultaneously actuatesaid trigger means and fire all of said guns when said firing controlcircuit is energized, a normally open circuit closing switch connectedin said electrical firing control circuit to normally interrupt thesame, and actuating means carried by and movable with the breech blockof the slower firing gun and engageable with said normally open circuitclosing switch to close said switch when the slower firing gun breechblock is in firing position and disengageable from said switch when saidslower firing gun breech block is in recoil position to allow saidswitch to move to its normally open position to interrupt the saidelectrical firing control circuit.

3. In a device of the class described, at least two machine guns, one ofwhich fires at a slower rate than the other gun, a'movable breech blockon each gun movable forwardly to firing position and movable rearwardlyto recoil position incident to firing of that gun, trigger means on eachgun for firing that gun,electro-magnetic trigger actuating means on eachgun engageable with the trigger means on that gun when energized toactuate the trigger means to fire that gun, an electrical firing controlcircuit connecting said electro-magnetic trigger actuating means tocause a simultaneous energizing of said electro-magnetic triggeractuating means and simultaneous actuation of the trigger means to firesaid guns simultaneously, normally open circuit closing switch meansrelatively fixed on the slower firing gun with respect to the breechblock movement thereof and electrically connected in said electricalfiring control circuit'to normally interrupt the same,

actuator fixed on said slower firing gun breech block in switch closingengagement with said norengage the said normally open circuit closingswitch means to allow said switch means tojopen and interrupt'saidfiring control circuit when said block and switch actuslower firing gunbreech ator are in recoil position. I

FRITS JAN WILLEM DEN OUDEN.

a switch closing

